Blackwell's Five-Minute Veterinary Consult: Reptile and Amphibian. Javier G. Nevarez

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       Herpesvirus infections

       Bacterial and/or fungal infections

       In the United States, all the ranaviruses described in reptiles to date have been genetically closely related, and a highly sensitive real‐time PCR is available for their detection.

       In other parts of the world, ranaviruses found in reptiles have been more genetically diverse, and PCRs capable of detecting these should be used.

       These viruses can also be relatively easily isolated in cell culture.

       Oral and cloacal swabs have been used to detect ranaviruses, as has blood, more invasive samples (tail clips, tissue biopsies) may be more sensitive.

       The liver and kidneys should also be tested if possible.

       An ELISA has been described for the detection of antibodies against ranaviruses in chelonians, although this is not widely commercially available.

       Chelonians with ranavirus infections have been described with hepatitis, enteritis, and pneumonia.

       Vasculitis and formation of thrombi in various organs has also been described.

       In some, but not all, cases, infection may be associated with basophilic intracytoplasmic inclusions in in affected cells, especially hepatocytes and epithelial cells of the upper gastrointestinal tract.

       There is no specific treatment available for iridovirus infections in reptiles.

       All viruses in this family replicate at temperatures below 32 degrees C (89.6 degrees F), and environmental temperature has been shown to influence the pathogenicity of ranaviruses in turtles.

       It is, however, important to keep the POTZ of the affected species in mind when adjusting environmental temperature.

       Ranaviruses can be transmitted between various ectothermic vertebrate classes, and care should be taken not to mix species.

       Quarantine procedures for all ectothermic vertebrates in a collection should include testing for ranaviruses.

       Since wild reptiles and amphibians can be infected, and ranaviruses may survive for some time in the environment, especially under cold conditions, introduction of virus into a collection via the environment (e.g., water, soil) should be avoided.

       Conversely, in the case of an outbreak, special care should be taken to avoid contamination of the environment. All water and substrate that comes into contact with infected animals should be disinfected before it is disposed of, as should all husbandry items.

       Carcasses from dead animals should be disposed of appropriately, ensuring that they do not come in contact with other animals.

       Since ectoparasites may play a role in the transmission of various iridoviruses, effective measures for parasite control should be implemented.

       Ranaviruses appear to be very infectious in chelonians, and affected animals should be barrier nursed.

       Viruses can cross species and class barriers, so contact with any other ectothermic vertebrates should be avoided.

       In has been suggested that ranaviruses may be transmitted by hematophagous invertebrates, so control of mosquito populations may be helpful.

       The time to development of disease in contact animals can vary depending on the route of infection, amount of infectious material, virus strain and host species, so monitoring should be continued for several weeks to months in an affected collection.

       Surviving infected animals can become carriers.

       Morbidity is usually very high, although recovery from infection has been described.

       Surviving animals may remain carriers and should be kept separate from susceptible animals including reptiles, amphibians, and fish.